package com.mall.order.biz.handler;

import com.mall.commons.tool.exception.BizException;
import com.mall.order.biz.context.CreateOrderContext;
import com.mall.order.biz.context.TransHandlerContext;
import com.mall.order.constant.OrderRetCode;
import com.mall.order.dal.entitys.Stock;
import com.mall.order.dal.persistence.StockMapper;
import com.mall.order.dto.CartProductDto;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.CollectionUtils;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @Description: 扣减库存处理器
 * @Author： wz
 * @Date: 2019-09-16 00:03
 **/
@Component
@Slf4j
public class SubStockHandler extends AbstractTransHandler {

    @Autowired
    private StockMapper stockMapper;

	@Override
	public boolean isAsync() {
		return false;
	}

	@Override
	@Transactional
	public boolean handle(TransHandlerContext context) {
		CreateOrderContext createOrderContext= (CreateOrderContext) context;
		List<CartProductDto> dtoList = createOrderContext.getCartProductDtoList();
		List<Long> productIds = new ArrayList<>();


		if (CollectionUtils.isEmpty(productIds)){
			productIds = dtoList.stream().map(o -> o.getProductId()).collect(Collectors.toList());
		}
		productIds.sort(Long::compareTo);
		//锁定库存
		List<Stock> stockList = stockMapper.findStocksForUpdate(productIds);
		if (CollectionUtils.isEmpty(stockList)){
			throw new BizException("库存未初始化");
		}


		if (stockList.size() !=productIds.size()){
			throw new BizException("部分商品未初始化");
		}
		 //扣减库存
		for (CartProductDto cartProductDto : dtoList){
			Long productId = cartProductDto.getProductId();
			Long productNum = cartProductDto.getProductNum();

			/**
			 * 商品购买数量不能超过限购
			 */
			Stock stock1 = stockMapper.selectStock(productId);
			if (productNum > stock1.getRestrictCount()){
				throw new BizException(OrderRetCode.PURCHASE_LIMITATION.getCode(),OrderRetCode.PURCHASE_LIMITATION.getMessage());
			}

			Stock stock = new Stock();
			stock.setItemId(productId);
			stock.setLockCount(productNum.intValue());
			 stock.setStockCount(-productNum);

			stockMapper.updateStock(stock);
		}
		return true;
	}
}